Criteria and techniques of device-grade thin film silicon deposition for high efficiency solar cells developed in Panasonic/Sanyo were reviewed. By applying these techniques, record efficiencies were achieved for a-Si single junction, a-Si/a-SiGe tandem junction. We have also fabricated very high-efficiency a-Si/mu c-Si tandem solar cells and modules with a very high mu c-Si deposition-rate (>2.0 nm/s) of device-grade mu c-Si layers using Localized Plasma Confinement CVD. (C) 2013 Elsevier B.V. All rights reserved.